Field of the Invention
The present invention relates to the technical field of magnetic resonance imaging, in particular a tensioning apparatus, a superconducting magnet and a magnetic resonance imaging apparatus.
Description of the Prior Art
In the prior art, a cooling vessel for a superconducting magnet used in a magnetic resonance imaging (MRI) scanner has the basic components of a superconducting magnet, a low-temperature holding apparatus, an outer vacuum vessel surrounding the low-temperature holding apparatus, a load-bearing support, and suspending elements. The superconducting magnet is disposed in the low-temperature holding apparatus, for the purpose of subjecting the superconducting magnet to low-temperature cooling by the low-temperature holding apparatus. The load-bearing support is used for supporting the superconducting magnet with the low-temperature holding apparatus suspended in the outer vacuum vessel by the suspending elements. Since a preload must be applied to the suspending elements, in order to ensure that all elements remain tensioned during an impact load and to ensure the vessel remains accurately aligned, threaded connecting pieces in the suspending elements, which are fastened during an assembly process step, are generally used to achieve the required preloading.
The torque needed to fasten the threaded pieces may be very large, and in certain applications, will exceed the capability of manual tools in the available space. Moreover, since the load-bearing support supports the superconducting magnet, the load-bearing support inevitably occupies the same space as the suspending elements. Thus, with an ever greater need for cooling vessels to satisfy demands for minimization of dimensions, the complicated nature of existing cooling vessel suspending elements and the assembly process steps thereof have led to an increase in manufacturing costs.